Abstract: The invention relates to radiation-curable, water-emulsifiable compounds containing isocyanate groups or capped isocyanate groups, and to their use.

Abstract: A cross-linked thermoplastic polyurea is formed by heating a mixture containing a thermoplastic urethane base material, a monomeric and/or polymeric di-isocyanate comprising between 1 to 10% of the total weight of the mixture, and a diamine comprising between 1 to 10% of the total weight of the mixture. A thermoplastic polyurethane may be formed by substituting hydroquinone for the diamine. The mixture is heated to a temperature within the range of 250° F. to 550° F. The heated mixture, which is flowable, is then injected into at least one injection molding device. The mixture is then cured at a temperature between 150° F. to 250° F. for a period of time between 2 and 36 hours. The cross-linked thermoplastic polyurethane/polyurea retains the excellent flowability characteristics of a thermoplastic urethane while the same time exhibits good abrasion, tensile strength, rebound, and compression set characteristics which are similar to those found in thermoset urethanes.

Abstract: The invention describes amphiphilic polymer compounds which are prepared by a) reacting a di-, tri- or tetraglycidyl compound (A) with an optionally unsaturated reactive component (B) consisting of C8-C28-fatty acid, a C8-C28-alcohol or a secondary C8-C28-amine, and allowing b1) the reaction product from stage a) to react further first with b1?) an aliphatic or aromatic polyisocyanate compound (C) b1?) and optionally then with a polyalkylene oxide compound (D), and b1?) reacting the reaction product from stage b1?) or optionally b1?) with a component (E) which is reactive towards isocyanates and has at least one OH, NH2, NH or SH group, or b2) allowing the reaction product from stage a) to react to completion with the reaction product of component (C) with component (E) and optionally (D) and (C), or b3) allowing the reaction product from stage a) to react to completion with the reaction product from component (C) and component (D) and optionally (C) and optionally the reaction product of component (C) and

Abstract: An aqueous coating composition having a 60° gloss of ?40 upon drying comprising a self-crosslinkable polyurethane obtained by the reaction of: (A) an isocyanate-terminated pre-polymer formed from components which comprise (i) 5 to 65 wt % of at least one organic polyisocyanate; (ii) 0.

Abstract: A golf ball having a core and at least one layer disposed about the core is disclosed. The at least one layer is formed from a composition having multiple reactive and/or non-reactive ingredients. At least one of these ingredients is a sterically hindered polyamine, preferably formed from an active hydrogen functional compound and an amine/acid ortho- or meta-substituted cyclic compound.

Abstract: A golf ball having a core and at least one layer disposed about the core is disclosed. The core may further include a center and an outer core layer disposed about the center. The layer is formed from a composition having a prepolymer and a curative, the prepolymer being formed from an isocyanate and a blend of two or more telechelic polyahls, wherein a first telechelic polyahl has a first functionality of 3 or greater, which is greater than a second functionality of a second telechelic polyahl in the blend. The layer displays an enhanced shear resistance.

Abstract: The invention relates to low-viscosity polyaddition compounds containing uretdione groups, preparation process, and use.

Abstract: An aqueous dispersion type polyurethane composition is obtained from (a) a polyisocyanate component essentially comprising a diisocyanate and optionally other polyisocyanate compound, (b) a polyol component essentially comprising a polycarbonate diol having an average molecular weight of 500 to 5000 and a carboxyl-containing diol and optionally other polyol compound, (c) an amine component essentially comprising a monoamine compound as an essential component and optionally a diamine compound, (d) a carboxyl-neutralizing component, and (e) water. The composition is suited as a member of automotive intercoating compositions, providing a coating film with good adhesion to surfaces to be coated and satisfactory physical properties. The coating film imparts sufficient impact resistance to coating systems.

Abstract: Rolls having a polyurethane elastomer formed from a polyurethane mixture, wherein the polyurethane mixture comprises polydiene, tri-functional polyol curative, an additional graft polymer curative having a molecular weight of at least about 800 and comprising diol, polyol, diamine, polyamine or a combination thereof, conductive modifier, antioxidant, and hydrolytic stabilizer. Methods of forming such rolls include casting the polyurethane mixture, followed by curing, then demolding, grinding to desired dimensions and baking such that the outer layer of the cured roll is oxidized.

Abstract: This invention relates to sprayable polyurethaneurea compositions, composite articles comprising at least one layer of these polyurethaneurea compositions and at least one layer of a polyurethaneurea foam forming composition, and to a process for the production of these composites.

Abstract: Aqueous polyurethane dispersions comprising polyurethane polymer and methods for making and using same are disclosed herein. In one aspect of the present invention, aqueous polyurethane dispersions, comprising a polyurethane polymer having a weight average molecular weight ranging from 20,000 to 80,000, are prepared by controlling the weight average molecular weight of the polymer by reacting the isocyanate terminated prepolymer with at least one chain terminating agent; and/or maintaining a N/COOH molar ratio of amine in the neutralizing agent to acid functional group in the isocyanate reactive compound to from about 0.5:1 to about 1:1.

Abstract: The invention provides a feed/transport roller formed of polyurethane material, which roller has high wear resistance as well as low hardness for providing excellent sheet feeding capacity and which meets a recent requirement; i.e., high durability for allowing high-speed operation. The feed/transport roller has an elastic layer formed of a castable polyurethane produced through reaction of a polyester-polyol having a number average molecular weight of 1,000 to 3,000 with a polyisocyanate, wherein the elastic layer is formed from the polyester-polyol, the polyisocyanate, an adipic acid ester derivative serving as a plasticizer, a short-chain diol having a molecular weight of 70 to 120 serving as a chain-extender, and a triol having a number average molecular weight of 3,000 to 5,000 serving as a cross-liking agent.

Abstract: An anti-bacterial polymer of the present invention consists of a vapor deposition-polymerization reaction product of a diaminobenzoic acid monomer or halogen atom-containing diamine monomer and a monomer reactive with these monomers. The anti-bacterial polymer can be prepared by a method, which comprises the step of subjecting a gas obtained by evaporating a diaminobenzoic acid monomer or halogen atom-containing diamine monomer and a gas obtained by evaporating a monomer reactive with these monomers to vapor deposition-polymerization, in a vacuum, to thus form an anti-bacterial polymer. The method permits the formation of a film having a desired thickness even on the surface having a complicated shape such as the surface of, for instance, a heat exchanger.

Abstract: Golf balls comprising thermoplastic, thermoset, castable, or millable elastomer compositions are presently disclosed. These compositions comprise at least one polymer having a plurality of amide linkages and a plurality of anionic moieties attached thereto. These compositions can be used in any one or more portions of the golf balls, such as inner center, core, inner core layer, intermediate core layer, outer core layer, intermediate layer, cover, inner cover layer, intermediate cover layer, and/or outer cover layer.

Abstract: Golf balls comprising thermoplastic, thermoset, castable, or millable elastomer compositions are presently disclosed. These compositions comprise at least one polymer having a plurality of amide linkages and a plurality of cationic moieties attached thereto. These compositions can be used in any one or more portions of the golf balls, such as inner center, core, inner core layer, intermediate core layer, outer core layer, intermediate layer, cover, inner cover layer, intermediate cover layer, and/or outer cover layer.

Abstract: Golf balls comprising thermoplastic, thermoset, castable, or millable elastomer compositions are presently disclosed. The compositions comprise at least one regioselective polyisocyanate having an asymmetric structure and comprising at least a first NCO group and a second NCO group, the first NCO group being substantially more sterically interfered than the second NCO group. The first NCO group is directly attached to a tertiary carbon atom or is one methine carbon atom away from either at least one quaternary carbon atom or at least two tertiary carbon atoms. These elastomer compositions can be used in any one or more portions of the golf balls, such as inner center, core, inner core layer, intermediate core layer, outer core layer, intermediate layer, cover, inner cover layer, intermediate cover layer, and/or outer cover layer.

Abstract: The present invention relates to new water-soluble polyaspartic esters and also to their use in aqueous coating compositions.

Abstract: Golf balls comprising thermoplastic, thermoset, castable, or millable elastomer compositions are presently disclosed. These elastomer compositions comprise reaction products of polyisocyanates and telechelic polymers having isocyanate-reactive end-groups such as hydroxyl groups and/or amine groups. These elastomer compositions can be used in any one or more portions of the golf balls, such as inner center, core, inner core layer, intermediate core layer, outer core layer, intermediate layer, cover, inner cover layer, intermediate cover layer, and/or outer cover layer.

Abstract: A novel method of manufacturing a golf ball. A golf ball made with this invention exhibits the characteristic feel and playability of a balata cover with superior durability characteristics (cut and shear resistance) which exceed those of a balata or ionomer cover.

Abstract: Low-cure powder coating compositions are disclosed. The compositions comprise a polyepoxide and a material having the structure wherein R1 is an organic radical having 6 to 25 carbon atoms; R2 is an organic radical having 1 to 20 carbon atoms; R3 and R4 are independently alkyl or phenyl groups having 1 to 8 carbon atoms; Z is oxygen or nitrogen, and when Z is oxygen R5 is absent and when Z is nitrogen R5 is hydrogen or is and n is 1 to 4. The material can optionally be reacted with an acidic hydrogen-containing compound. The compositions are curable without the use of crosslinking agents or accelerators. Methods for coating a substrate using these compositions, and substrates coated thereby, are also disclosed, as are additional catalysts useful for the same purpose.

Abstract: A phosphorus-containing urethane (meth)acrylate compound obtained by reacting (A) a polyol compound comprising (A1) a phosphorus-containing polyol having a phosphorus atom, with (B) a bifunctional or greater polyisocyanate and (C) a hydroxyl group-containing (meth)acrylate.

Abstract: Golf ball compositions, and components formed therefrom, including trifunctional materials, such as trifunctional isocyanates, polyols, and amines, that have improved performance and durability characteristics, e.g., improved heat resistance, improved resiliency, and dimensional stability.

Abstract: A novel composition useful for golf ball covers that comprises a blend of a dilsocyanate/polyol polyurethane prepolymer with a curing agent comprising a blend of slow-reacting diamine with a fast-reacting diamine such as dimethylthio 2,4-toluenediamine and diethyl 2,4-toluenediamine, respectively. A golf ball cover made with this composition exhibits the characteristic feel and playability of a balata cover with superior durability characteristics (cut and shear resistance) which exceed those of a balata or ionomer cover.

Abstract: The present invention relates to a method of preparing water-dispersible poly (urethane-urea) having aliphatic-aromatic isocyanate, more particularly to a method of preparing water-dispersible poly (urethane-urea) having aliphatic-aromatic isocyanate, with improved mechanical/thermal properties, such as heat resistance, chemical resistance and adhesion, good cost competitiveness and environmental friendliness, by reacting polyester polyol, dimethylol propionic acid and an aromatic isocyanate compound to obtain a hydroxyl (OH)-terminated prepolymer, adding an aliphatic isocyanate compound to said OH-terminated prepolymer to obtain an isocyanate (NCO)-terminated prepolymer wherein aromatic-aliphatic isocyanate is hybridized, neutralizing, water-dispersing and chain extending said NCO-terminated prepolymer.

Abstract: Golf ball compositions, and components formed therefrom, including trifunctional materials, such as trifunctional isocyanates, polyols, and amines, that have improved performance and durability characteristics, e.g., improved heat resistance, improved resiliency, and dimensional stability.

Abstract: The present invention relates to thermoplastically processable polyurethane elastomers (TPU) with tensile strengths of >35 MPa (measured in accordance with EN ISO 527-3), with shrinkages of <3% and with self-extinguishing properties based on the use of at least one flameproofing agent which can be built in, a process for their preparation and their use.

Abstract: Golf balls comprising thermoplastic, thermoset, castable, or millable elastomer compositions are presently disclosed. These elastomer compositions comprise reaction products of polyisocyanates and telechelic polymers having isocyanate-reactive end-groups such as hydroxyl groups and/or amine groups. These elastomer compositions can be used in any one or more portions of the golf balls, such as inner center, core, inner core layer, intermediate core layer, outer core layer, intermediate layer, cover, inner cover layer, intermediate cover layer, and/or outer cover layer.

Abstract: Golf balls comprising thermoplastic, thermoset, castable, or millable elastomer compositions are presently disclosed. These compositions comprise at least one fatty compound chosen from fatty polyamines and fatty polyamine telechelics. These elastomer compositions can be used in any one or more portions of the golf balls, such as inner center, core, inner core layer, intermediate core layer, outer core layer, intermediate layer, cover, inner cover layer, intermediate cover layer, and/or outer cover layer.

Abstract: Golf balls comprising thermoplastic, thermoset, castable, or millable elastomer compositions are presently disclosed. These elastomer compositions comprise at least one amine-terminated polyamide and at least one isocyanate-containing prepolymer. These elastomer compositions can be used in any one or more portions of the golf balls, such as inner center, core, inner core layer, intermediate core layer, outer core layer, intermediate layer, cover, inner cover layer, intermediate cover layer, and/or outer cover layer.

Abstract: At least one isocyanate-reactive monomer is reacted with an excess of molten monomeric diisocynate to produce at least one reaction product and a maximum of 0.5 wt % of free isocyanate groups. The reaction product is then mixed with at least 20 wt. %, based on the total weight of reaction product, of at least one isocyanate-terminated prepolymer which is essentially free of diisocyanate monomers and has a viscosity at 20° C. of at least 1.500 mPa·s, the isocyanate-terminated prepolymer having a content of free NCO groups of up to 25 wt % and containing a maximum of 0.1 wt. % of diisocyanate monomer(s) based on the weight of the isocyanate-terminated prepolymer. A polyurethane composition containing less than 0.1 wt. % of monomeric diisocyanate, based on the total weight of the resulting polyurethane composition, is produced.

Abstract: Novel polyurethanes containing sulfide groups which comprise at least one group of the general formula I in the polymer main chain and/or at least one group of the general formula II incorporated at the chain end: —X—A—S—B—Y—??(I) —X—A—S—B—YH??(II) in which the variables have the following definitions: S is the sulfur atom; X and Y independently of one another are oxygen atoms, sulfur atoms or groups —NZ where Z is the hydrogen atom or an alkyl radical of 1 to 10 carbon atoms; and A and B independently of one another are divalent organic radicals; novel polymer mixtures based thereon, and the use of the novel polyurethanes and polymer mixtures and dispersions thereof for the preparation of coating materials, adhesives and sealing compounds.

Abstract: The present invention relates to novel polyurethane prepolymers (PU prepolymers) of low viscosity containing NCO groups blocked with compounds containing phenol groups and to their use for producing polyurethane polymers. The PU prepolymers are prepared by reacting one or more diisocyanates or polyisocyanates with at least one isocyanate-reactive compound with a functionality of at least 1.5 to form an NCO-functional polyurethane prepolymer and subsequently blocking the free NCO groups with at least one hydrocarbon resin containing phenolic OH groups and/or one optionally substituted phenol in the presence of a catalyst which comprises at least one triorganoamine.

Abstract: Golf balls comprising thermoplastic, thermoset, castable, or millable elastomer compositions are presently disclosed. These elastomer compositions comprise at least one poly(urethane-co-urea) prepolymer and at least one curative. These elastomer compositions can be used in any one or more portions of the golf balls, such as inner center, core, inner core layer, intermediate core layer, outer core layer, intermediate layer, cover, inner cover layer, intermediate cover layer, and/or outer cover layer.

Abstract: A golf ball comprising at least one thermoplastic, thermoset, castable, or millable material formed from a composition comprising at least one telechelic polycarbonate having a generic structure of: where R1 and R2 independently include hydrogen, alkyl, aryl, aralkyl, alicyclic, cycloalkyl, and alkoxy groups; R3 to R6 independently include linear, branched, cyclic, aliphatic, alicyclic, araliphatic, aromatic, and ether moieties having 2–60 carbon atoms; x is 1 to 200; and y and z are independently 0 to 200.

Abstract: The present invention is directed to a novel method of preparing a polymerizate, which includes the step of polymerizing a two-component composition, which includes: a first component containing at least one polycyanate reactant having at least two functional groups selected from isocyanate, isothiocyanate and combinations thereof, the polycyanate reactant being the reaction product of: a polythiol monomer having at least two thiol groups; and a polycyanate monomer having at least two functional groups selected from isocyanate, isothiocyanate and combinations thereof; and a second component containing at least one polyamine reactant having at least two functional groups selected from primary amine, secondary amine and combinations thereof. The molar equivalent ratio of (NCO+NCS) groups from the first component to (—NH2+—NH—) groups from the second component is from 0.5 to 100. The present invention is also directed to polymerizates prepared according to the method of the present invention.

Abstract: The present invention is directed to a novel method of preparing a polymerizate, which includes the step of polymerizing a two-component composition, which includes: a first component containing at least one polycyanate reactant having at least two functional groups selected from isocyanate, isothiocyanate and combinations thereof, the polycyanate reactant being the reaction product of: a polythiol monomer having at least two thiol groups; and a polycyanate monomer having at least two functional groups selected from isocyanate, isothiocyanate and combinations thereof; and a second component containing at least one polyamine reactant having at least two functional groups selected from primary amine, secondary amine and combinations thereof. The present invention is also directed to polymerizates prepared according to the method of the present invention. The present invention is further directed to photochromic articles that may be prepared from the polymerizates of the present invention.

Abstract: Disclosed herein is a blocked mercaptosilane selected from the group consisting of [[(ROC(?O))p—(G)j]k—Y—S]r—G—(SiX3)s; and??(1) [(X3Si)q—G]a—[Y—[S—G—SiX3]b]c??(2) wherein Y is a polyvalent species (Q)zA(?E) selected from the group consisting of —C(?NR)—; —SC(?NR)—; —SC(?O)—; —OC(?O)—; —S(?O)—; —S(?O)2—; —OS(?O)2—; (—NR)S(?O)2—; —SS(?O)—; —OS(?O)—; (—NR)S(?O)—; —SS(?O)2—; (—S)2P(?O)—; —(—S)P(?O)—; —P(?O)(—)2; (—S)2P(?S)—; —(—S)P(?S)—; —P(?S)(—)2; (—NR)2P(?O)—; (—NR)(—S)P(?O)—; (—O)(—NR)P(?O)—; (—O)(—S)P(?O)—; (—O)2P(?O)—; —(—O)P(?O)—; —(—NR)P(?O)—; (—NR)2P(?S)—; (—NR)(—S)P(?S)—; (—O)(—NR)P(?S)—; (—O)(—S)P(?S)—; (—O)2P(?S)—; —(—O)P(?S)—; and —(—NR)P(?S)—; wherein the atom A attached to unsaturated heteroatom E is attached to the sulfur which in turn is linked via a group G to the silicon atom; each R is chosen independently from hydrogen, straight, cyclic, or branched alkyl that may or may not contain unsaturation, alkenyl groups, aryl groups, and aralkyl groups, with each R containing from 1 to 18 c

Abstract: A polyurethane resin which is the reaction product of at least one diisocyanate and a group of components having isocyanate reactive functional groups. The group of components includes a first group of one or more polyether polyols each having an average molecular weight in the range of 1000 to 10000 g/mol, a second group of one or more polyether polyols each having an average molecular weight in the range of 400 to 10000 g/mol and being hydrophilic and water-soluble, a third group of one or more polyols each having an average molecular weight equal to or less than 800 g/mol, at least one amine, and a reaction terminating agent. The ratio of the equivalent weights of the diisocyanate to the components having isocyanate reactive functional groups is selected such that essentially all of the isocyanate groups of the diisocyanate are present only as the reaction product with one of said isocyanate reactive functional groups.

Abstract: Triazine ring based polymers for photoinduced liquid crystal alignment introduces photoactive groups for inducing, reinforcing, improving and preserving liquid crystal alignment, for example photoreactor such as cinnamate, coumarin, chalcone and maleimide, as a chain to have at least one photoactive group. One of the photoactive groups can experience Fries rearrangement which induces liquid crystal alignment, and other groups can experience photodimerization, photoisomerization, photocrosslinkng or photodegradation to reinforce, change or preserve the generated alignment.

Abstract: Isocyanate-functional polyurethane prepolymers and aqueous dispersions therefrom which are useful for the production of flat materials having excellent resistance to alcoholic solvents are described. The prepolymers are prepared by reacting: A) an isocyanate selected from the group consisting of i) an aliphatic and/or a cycloaliphatic isocyanate, ii) a mixture of an aromatic isocyanate and an aliphatic and/or a cycloaliphatic isocyanate, B) a di- or polyhydroxy compound having a number average molecular weight of from 700 to about 16,000, and C) optionally, a dihydroxy and/or polyhydroxyl compound having a number average molecular weight of less than 700, with the provisos that a) at least one of components A), B or C) has a functionality of more than 2 and b) if both component A) and component B) are difunctional, component C) cannot be a trihydroxy component of the formula: R—(OH)3 ?where R is a saturated straight chain or branched chain aliphatic group of from 2 to 8 carbon atoms.

Abstract: A golf ball comprising a layer including a saturated polyurethane composition formed of a saturated prepolymer and a saturated curing agent, wherein the layer may be casted as an outer cover, formed as an intermediate layer, or both.

Abstract: Polyurethane and polyurea compositions for golf balls with improved stability of the curative blend, wherein the curative blend includes a pigment, a curing agent, and a compatible freezing point depressing agent so that the curative blend has a lower freezing point than the curing agent by itself and the blend does not lose pigment dispersion upon solidification and subsequent thawing.

Abstract: A process for preparing polyisocyanate prepolymers containing allophanate structural units that includes reacting a) one or more polyisocyanates with b) one or more polyetherpolyols containing less than or equal to 0.02 milliequivalent of unsaturated end groups per gram of polyol and having a polydispersity of from 1.0 to 1.5 and/or an OH functionality of greater than or equal to 1.9 ?to provide an NCO-functional polyurethane prepolymer containing urethane groups that are partly or fully allophanatized by further reaction with c) polyisocyanates, which may be different from those from a), and d) catalysts and optionally adding e) acidic additives before, during and/or after the allophanatization. The polyisocyanate prepolymers can be used to produce coatings, adhesive bonds and/or seals. The coatings include one or more of the polyisocyanate prepolymers, and at least one diol or polyol and/or at least one linear and/or cyclic, aliphatic, araliphatic and/or aromatic diamine or polyamine.

Abstract: Melt spun thermoplastic polyurethane polymers useful as textile fibers and having good tenacity and recovery and substantially no gelation are disclosed. The polymers are prepared by a three-step polymerization process including: preparation of “hard” segment oligomer, preparation of “soft” segment oligomer and final reaction of “hard” segment with “soft” segment in a twin-screw reaction extruder to obtain a final polyurethane product having relatively uniform distances between the “hard” segments. The “soft” segment oligomer comprises blocks of polymeric glycol (poly) urethanes end capped with isocyanate groups. The “hard” segment oligomer comprises blocks of low molecular weight C2–C6 glycol (poly) urethanes.

Abstract: The present invention provides polyamines which contain urea groups, a process for the preparation thereof and their use to produce adhesives, sealants, embedding compounds, moulded items or coatings.

Abstract: Cationic polyurethanes and polyureas formed from (a) at least one diisocyanate or reaction product thereof with one or more compounds containing two or more active hydrogen atoms per molecule, and (b) at least one diol, primary or secondary amino alcohol, primary or secondary diamine or primary or secondary triamine each with one or more tertiary, quaternary or protonated tertiary amine nitrogen atoms and having a glass transition temperature of at least 25° C. and an amine number of from 50 to 200, based on the non-quaternized or -protonated compounds, or other salts of these polyurethanes and polyureas, are useful as ingredients of cosmetic and pharmaceutical preparations.

Abstract: A golf ball including a core and a cover layer, where the cover layer includes a curing agent and a polyurethane/urea hybrid prepolymer formed from a polyisocyanate and a monodisperse heterotelechelic polymer having a polydispersity of from about 1.0 to about 1.

Abstract: A golf ball comprising a core and a cover, wherein the core or the cover comprises a thermoplastic or thermoset composition comprising a polyurea prepolymer formed from a reactant A comprising an isocyanate; and a reactant B comprising a polyether polyamine having a repeating branched oxyalkylene monomer unit, or a polymerized polyamine formed from a chiral diol or a chiral cyclic ether.

Abstract: A golf ball including a core and a cover layer including a curing agent and a polyurethane prepolymer formed from a polyisocyanate and a monodisperse telechelic polyol having a polydispersity of from about 1.0 to about 1.3, and having the formula: T-Zn-C-Y-C-Zn-T where Y is at least one molecule or mixtures of molecules having at least two independently polymerized vinyl groups, such as 1,3-divinylbenzene or 1,4-divinylbenzene; C is a hydrogenated or unsaturated block derived by anionic polymerization of at least one monomer selected from the group consisting of conjugated dienes, alkenyl-substituted aromatics, and mixtures thereof; Zn is a branched or straight chain hydrocarbon connecting group which contains n=1–50 carbon atoms; and T is hydroxyl.

Abstract: A golf ball including a core and a cover layer including a curing agent and a polyurea prepolymer formed from a polyisocyanate and a monodisperse telechelic polyamine having a polydispersity of from about 1.0 to about 1.3, and having the formula: T-Zn-C—Y—C-Zn-T where Y is at least one molecule or mixtures of molecules having at least two independently polymerized vinyl groups, such as 1,3-divinylbenzene or 1,4-divinylbenzene; C is a hydrogenated or unsaturated block derived by anionic polymerization of at least one monomer selected from the group consisting of conjugated dienes, alkenyl-substituted aromatics, and mixtures thereof; Zn is a branched or straight chain hydrocarbon connecting group which contains n=1–50 carbon atoms; and T is primary or secondary amine.